Problem: $ { \left[\begin{array}{rr}{3} & {-1} \\ {4} & {0} \\ {0} & {1}\end{array}\right]-\left[\begin{array}{rr}{3} & {4} \\ {1} & {0} \\ {1} & {1}\end{array}\right] = {?} } $
To find the difference of two matrices, subtract the corresponding items between each matrix. ${\left[\begin{array}{rr}{3}-{3} & {-1}-{4} \\ {4}-{1} & {0}-{0} \\ {0}-{1} & {1}-{1}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{0} & {-5} \\ {3} & {0} \\ {-1} & {0}\end{array}\right]}$